Micro satellite subwoofer plans

[BasicHIFI1]

PC speaker systems consisting of satellite subwoofers sound quite good considering their price and size. I want to build such a system, actually I want to build the ported subwoofer box that comes with these systems but I see no plans on how to do this. Typically one of these boxes has one driver of about 4 inches and a port on one side, is solid and heavy.

Ideally I would want one that is ony 10 cm deep that can be hung on a wall but
I am willing to compromise with a sqaure box that I can fix under my desk. Finding decent full ranges is not the problem it's getting bass out of a system that is the challenge.

To summarise: the design will be two small 3 inch full range open baffles with sealed mini subwoofer in between.

 

[BasicHIFI1]

Something like this

From a Google search.

 

[keilau]

PC speaker systems consisting of satellite subwoofers sound quite good considering their price and size. I want to build such a system, actually I want to build the ported subwoofer box that comes with these systems but I see no plans on how to do this. Typically one of these boxes has one driver of about 4 inches and a port on one side, is solid and heavy.

Ideally I would want one that is ony 10 cm deep that can be hung on a wall but
I am willing to compromise with a sqaure box that I can fix under my desk. Finding decent full ranges is not the problem it's getting bass out of a system that is the challenge.

To summarise: the design will be two small 3 inch full range open baffles with sealed mini subwoofer in between.

Unfortunately, it is very hard to get low bass extension with a sealed box mini sub. The closed cabinet size will be unmanageable (too big).

I found 2 mini sub DIY project from authors that I respect and trust, both used vented design:

http://www.rjbaudio.com/Cerberus/cerberus.html* (Roman J Bednarek)

Voxel - a mini-sub+ - Techtalk Speaker Building, Audio, Video Discussion Forum (Paul Carmody)

Both used the Tang Band W6-1139SIF 6-1/2" Paper Cone Subwoofer Speaker, which allowed an exceptional bass and power handling at very moderate driver cost, $52.50 at Parts Express. (Carmody originally used the Tang Band 5" and some reader built with the 6.5" in the later post of the TechTalk thread.)

The cabinet cost is small. A 12"x8' MDF bookshelf board plus some labor is sufficient. You may build it as passive or with a plate amplifier. I like the MCM Subwoofer Plate Amplifier (MCM Part #50-6269) if I decide to go active. It is a traditional analogue amp design with a large toroidal transformer. It should have much lower distortion and better damping factor at the low bass region when compared to Class D plate amplifier. You may need to modify the cabinet size slightly to accommodate the plate amplifier.

 

[BasicHIFI1]

Thats about what I was looking for, but I will be using my off the shelf speakers to start with and experiment. Need to post the 3d image of the design soon.

 

[Jerms]

Unfortunately, it is very hard to get low bass extension with a sealed box mini sub. The closed cabinet size will be unmanageable (too big).

I found 2 mini sub DIY project from authors that I respect and trust, both used vented design:

http://www.rjbaudio.com/Cerberus/cerberus.html* (Roman J Bednarek)

Voxel - a mini-sub+ - Techtalk Speaker Building, Audio, Video Discussion Forum (Paul Carmody)

Both used the Tang Band W6-1139SIF 6-1/2" Paper Cone Subwoofer Speaker, which allowed an exceptional bass and power handling at very moderate driver cost, $52.50 at Parts Express. (Carmody originally used the Tang Band 5" and some reader built with the 6.5" in the later post of the TechTalk thread.)

The cabinet cost is small. A 12"x8' MDF bookshelf board plus some labor is sufficient. You may build it as passive or with a plate amplifier. I like the MCM Subwoofer Plate Amplifier (MCM Part #50-6269) if I decide to go active. It is a traditional analogue amp design with a large toroidal transformer. It should have much lower distortion and better damping factor at the low bass region when compared to Class D plate amplifier. You may need to modify the cabinet size slightly to accommodate the plate amplifier.

<cough> Voxel uses the W5.

I would also say that these two designs are reputed to work well until the power is cranked up. Ports on both designs are below optimal size for high output and will generate port noises when pushed (not usually a situation for a near-field system, I hope. Just don't go planning to use them as a party system over the holiday period ).

 

[djn]

For a small room you should build 3 or 4 subs. Multiple subs will flatten the signal and it should sound right wherever you sit.

 

[BasicHIFI1]

Optimized for low SPLs

<cough> Voxel uses the W5.

I would also say that these two designs are reputed to work well until the power is cranked up. Ports on both designs are below optimal size for high output and will generate port noises when pushed (not usually a situation for a near-field system, I hope. Just don't go planning to use them as a party system over the holiday period ).

Power or lack of it is not pronlem, I usually listen at 70-80 dB SPL at 1 metre. Apparently as loud as a vacuum cleaner: Vacuum cleaner, distance 1 m.

Table chart sound pressure levels SPL

I would like to optimize the system for those levels, with full sound including bass. The Equal Loudness Countours means some distortion free equalization will be required.

 

[eriksquires]

When you say you want mini, can you deal with a 5" woofer in a 2 way for your satellites? If so, You can try these, they are tuned for desktop or bookshelf use, as opposed to stand mounts.

https://speakermakersjourney.blogspot.com/2016/02/the-lm-1-bookshelf-version.html

On a bookshelf you will find bass to 50-60 Hz, but on a desk only about 100 due to reinforcement from the rear and the rear port. For a PC you will definitely need a sub. You don't have to get very complicated, as there are several good 10-12" woofers that will work well in a 1cubic foot enclosure.

Best,

Erik

 

[BasicHIFI1]

Erik

The system is to be wall-mounted, a small detail I forgot to mention. Two open baffle satellites, and 3.5 to 4 inch, mounted on the wall behind my desk (more deskspace) and the subwoofer mounted on the wall - somewhere in between. A mini version of my Wall mounted open baffle (thread).

My experiments with open baffle have been very very encouraging, but it would be nice to get a decent bass response hence the subwoofer. It's all about convenience, building one box as opposed to two.

The sat/sub systems I am hearing these days are really very good, with good bass, and a really nice meshing of the two response curves from the full range tweeters and the sub. Voices sound close to natural, and the satellites at ear level (this is vital) or pointing directly at the ears makes for good clarity.

 

[Patrick Bateman]

An externally hosted image should be here but it was not working when we last tested it.

We were discussing this in another thread, but Nola already sells what you describe. I heard it at CES 2016 and it's fabulous.

IMHO, the drivers in the satellites are Peerless TC9 ($15) and the sub is a Dayton Reference 8. ($100)

So you could build the whole thing for under $200 if you keep the cabinet cost low.

Here's some data on it:

" At AXPONA 2016 Nola Speakers will be showcasing its new Brio Trio satellite/subwoofer system ($2,700) and demonstrating its Studio Grand Reference Gold floorstanding loudspeaker, which are two compact ultra high-end models that incorporate unique drivers and design attributes to deliver extraordinary musical accuracy. The Brio Trio will be on exhibit within the Manufacturer's Showcase and in Room 402 at the hotel.

The Nola Brio Trio satellite/subwoofer loudspeaker system is a compact, three-piece package featuring Nola's hallmark open baffle design and a novel 1.5-way enclosure for the main speakers. The Brio Trio lives up to its name with dynamic realism that the manufacturer feels far exceeds its compact size of 5.5" x 5.5 x 12" for the satellites. Available in Gloss Black, it's ideal for use as a desktop monitor system or a top-quality 2.1-channel system where space is limited yet uncompromising sound is desired.



Nola Brio Trio Satellite/Subwoofer System



The Brio main speaker employs two identical 3.5" drivers, with the upper driver operating in an open baffle as a dipole and the lower driver mounted in a ported chamber. This configuration combines the natural imaging and expansive soundstage provided by the open baffle mounting with the dynamic presence and impact of the enclosure-mounted driver.

The drivers feature a special paper cone/surround design for reduced resonance and a copper pole piece cap that reduces distortion that could otherwise result from unwanted modulation of the motor assembly’s magnetic field. These factors, combined with a low moving mass enables the drivers to provide smooth frequency response to 20 kHz.

The matching subwoofer utilizes an 8" high-power-handling bass driver in a sealed enclosure, powered by a Class A/B 250-watt amplifier. Nola President/CEO Carl Marchisotto chose Class A/B rather than the more typically used Class D subwoofer amp topology because of the A/B design's superior sound quality. The subwoofer provides continuously variable level and crossover frequency controls (from 40Hz – 180Hz, 24dB/octave), 6dB at 35Hz switchable EQ, a phase switch and line-level and speaker-level inputs, enabling it to be seamlessly matched to the Brio main speakers and deliver optimum performance in any system and room."

 

[BasicHIFI1]

Thanks Patrick, that's a great system with $15 drivers. Once I get things sorted out I think I will be spending a bit more on the drivers. I also need to get my noexistent woodworking skills upto an acceptable level. So it's all experimentation now.

I like those ribbon cables used in the system, though. The idea of using one open baffle and one in a ported box. Must make for some interesting interference patterns between the two drivers.

Are you aware of any wall-mounted mini satellite subwoofer systems? I have not been able to find any online.

 

[djn]

I just looked. The Peerless TC9 is on sale for 11 bucks. Looks like a great speaker for the money.

As for wall mounted subs, I've never heard of it, but it be just a matter of mounting them on the wall.

The issue might be that it could turn the wall into a resonator and give unwanted peaks or phase distortion.

 

[BasicHIFI1]

I just looked. The Peerless TC9 is on sale for 11 bucks. Looks like a great speaker for the money.

As for wall mounted subs, I've never heard of it, but it be just a matter of mounting them on the wall.

The issue might be that it could turn the wall into a resonator and give unwanted peaks or phase distortion.

We have brick walls here. More difficult to drill stuff into.

https://www.quora.com/Why-are-house...s-such-as-India-are-made-from-concrete-or-tin

The Vifa looks great, the whole point is that I want to get my cabinets and stuff sorted out before I start messing around with a world class speaker.

 

[BasicHIFI1]

The Vifa will cost me about $30 including shipping of $5 and taxes of $8 or so! Worth it.

 

[BasicHIFI1]

Essential to a subwoofer is the crossover. There is an online crossover calculator here that outputs some values and a nice diagram.

I should try a first order I guess. Lots to read up there.

Gives the following for a 400Hz crossover frequency, 4 ohm drivers.

Capacitors
C1 = 99.38 uF
Inductors
L1 = 1.59 mH

 

[BasicHIFI1]

Planning to build prototype out of corrugated cardboard computer box

Some older threads:

http://www.diyaudio.com/forums/subwoofers/251430-proposal-cardboard-sub-test-enclosure.html

http://www.diyaudio.com/forums/subw...amboard-12v-high-efficiency-low-cost-sub.html

http://www.diyaudio.com/forums/planars-exotics/43353-cardboard-speakers.html

and DIY

https://www.techwillsaveus.com/resources/build-diy-speakers-cardboard-box/
cardboard mini speaker system - All

https://www.techwalla.com/articles/how-to-make-a-speaker-box-from-a-cardboard-box

https://www.amazon.com/OrigAudio-Recycled-Speakers-Standard-Daydream/dp/B003NVM920

And a radio. Good idea for an amp enclosure

Cardboard Radio : Card iPod speaker with great sound.

 

[adason]

I built NOLA Brio, just for fun, as I had TC9 at hand. They sound nice for small cute little speakers.

 

[BasicHIFI1]

I have this Bluetooth speaker:

Sony SRS-XB10 Bluetooth Speaker (Blue) SRSXB10/BLUE B&H Photo

The specs say it has one passive radiator as well as the main speaker and puts out 5 Watts. I have tested it the other day with a tone generator

Online Tone Generator - generate pure tones of any frequency

and it goes down to not quite 20Hz but about 60 if I remember and was very impressive, though a bit distorted at those levels.

Any speaker I build will have to match these levels if possible, but I do not have 5 Watts, though a CD player will output a lot of punch, as I have seen personally.

 

[BasicHIFI1]

Components and layout

I intend to use the Radio Shack woofers I have, listed as having a frequency response from 50 to 6,000 HZ.

The basic layout of the system is shown below (Wings 3D). The subwoofer will be attached to the underside of the desk, out of the way, and the FR speakers will be added on either side of the desk on the wall or mounted on a stand on the desk. They will be open baffle.

 

[BasicHIFI1]

Fixing a speaker 12 cm from the rear wall enhances the lower frequencies a little, much better than with their 'back against the wall'.

Interesting related thread is here:

Small open-baffle?